In Lewis v. United States (1892), 146 U.S. 370, 13 S.Ct. 136, 36 L.Ed. 1011, the United States Supreme Court reviewed this most fundamental of rights and clearly and succinctly stated: "A leading principle that pervades the entire law of criminal procedure is that, after indictment is found, nothing shall be done in the absence of the prisoner." Id. at 372. The court then went on passionately to state that the exclusion of the defendant from part of the proceedings is "'contrary to the dictates of humanity.'" Id., quoting Prine v. The Commonwealth (1851), 18 Pa. 103. This remains good law today. In Joint Anti-Fascist Refugee Commt. v. McGrath (1951), 341 U.S. 123, 71 S.Ct. 624, 95 L.Ed. 817, Justice Felix Frankfurter in his concurring opinion noted that "the plea that evidence of guilt must be in secret is abhorent to free men." Id. at 170 (Frankfurter, J., concurring). In Lewis v. United States, 385 U.S. 206, 17 L. Ed. 2d 312, 87 S. Ct. 424 (1966), a federal agent posed as a drug buyer and was admitted into the defendant's home, where he purchased drugs. The Supreme Court noted that the defendant "invited the undercover agent to his home" and that the agent did not "see, hear, or take anything that was not contemplated, and in fact intended, by the defendant as a necessary part of his illegal business." Lewis, 385 U.S. at 210, 17 L. Ed. 2d at 315-16, 87 S. Ct. at 427. In Lewis v. United States, 445 U.S. 55, 56, 100 S. Ct. 915, 916, 63 L. Ed. 2d 198 (1980), the United States Supreme Court addressed "the question whether a defendant's extant prior conviction, flawed because he was without counsel, . . . may constitute the predicate for a subsequent conviction under the former federal firearms statute, 18 U.S.C. app. 1202(a)(1)" (1976). Based primarily on the statute's clear language and "plain meaning," the Court concluded that "the fact of a felony conviction imposes a firearm disability until the conviction is vacated or the felon is relieved of his disability by some affirmative action." 445 U.S. at 60-61, 100 S. Ct. at 918. The Court "viewed the language Congress chose as consistent with the common-sense notion that a disability based upon one's status as a convicted felon should cease only when the conviction upon which that status depends has been vacated." Id. at 61 n.5, 100 S. Ct. at 918 n.5. The Court in Lewis noted that the federal firearms statute contained "no exception . . . for a person whose outstanding felony conviction ultimately might turn out to be invalid for any reason." Id. at 62, 100 S. Ct. at 919. Accordingly, the Court held that the statute "prohibits a felon from possessing a firearm despite the fact that the predicate felony may be subject to collateral attack on constitutional grounds." Id. at 65, 100 S. Ct. at 921. In so holding, the Court distinguished three prior cases in which it had disallowed use of constitutionally invalid convictions "to impeach the general credibility of the defendant," to "sentence a defendant after a subsequent conviction," and to enhance "punishment under a State's recidivist statute." Id. at 59-60, 100 S. Ct. at 918.